Insulating floor underlayment

ABSTRACT

A flooring material having a textile pad substructure with a density of greater than 13 pounds per cubic foot is provided. The textile pad has reinforcement and binding fibers. The binding fibers are thermoplastic and are used to bind the reinforcement fibers together. The pad is created by heating and compressing a fibrous textile batt so that it has a density of greater than 13 pounds per cubic foot.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a continuation-in-part of U.S. applicationSer. No. 09/535,802 filed on Mar. 28, 2000. The disclosure of the aboveapplication is incorporated herein by reference.

FIELD OF THE INVENTION

[0002] The present invention relates generally to a textile pad forlaminate floor underlayment. More specifically, the invention relates toa textile pad which is used under laminate or ceramic floors to improveacoustic and thermal insulation properties as well as crack resistance.

BACKGROUND OF THE INVENTION

[0003] Textile pads are widely used in flooring applications. A pad isdesirable when wood flooring is applied over a sub flooring. These padsused in flooring applications serve multiple purposes. They may absorbimpact, such as from persons walking on the flooring. They may providesound deadening, and may provide insulating properties against heattransfer. Pads also may accommodate roughness, unevenness, or otherflaws in the sub flooring, and may provide a barrier against moistureand dirt. Finally, pads may lessen impact stresses on the flooring tolengthen the life of the flooring and make the flooring appear to bemore durable and of a higher quality.

[0004] In the related art, textile pads are not used under ceramicflooring. This is because a pad would have to be relatively thin so asto not cause any unevenness in transition areas (i.e., areas of flooringtype transition, such as in doorways, etc.). Furthermore, ceramic tilestraditionally must be placed on a solid floor substructure to preventcracking of the tile or the adhesive or tile grout.

[0005] What is needed, therefore, are improvements in methods andapparatus for forming textile pads for a laminate floor underlayment aswell as a textile pad which can be used under a ceramic tile floor.

SUMMARY OF THE INVENTION

[0006] A flooring material having a textile pad substructure with adensity of greater than 13 pounds per cubic foot is provided accordingto a first aspect of the invention. The insulative textile flooring padhas reinforcement fibers and binding fibers. The binding fibers arethermoplastic fibers which are melted to couple the binding fibers andreinforcement fibers together. The binding fibers are selected from thegroup of polyethylene, polyester, polypropylene, and mixtures thereof.

[0007] Further, a flooring structure is disclosed. The flooringstructure has a sub floor, a surface layer, and an insulative paddisposed between the sub floor and the surface layer. The insulative padhas binder and reinforcement fibers distributed uniformly and randomlywithin a first plane. The binder fibers are meltable at a predeterminedtemperature to couple the binding fibers to the reinforcement fibers.

[0008] Further disclosed is a floor underlayment for disposal under afloor surface. The floor underlayment has less than 20% thermoplasticbinder fibers and more than 80% reinforcement fibers. The floorunderlayment has a first surface disposed adjacent to the floor surfaceand has a density of greater than 13.3 pounds per cubic foot.

[0009] Further disclosed is an apparatus for forming a plurality oftextile pads from a textile batt according to another aspect of theinvention. The apparatus comprises a pair of feed rollers for receivinga textile batt, a splitting knife downstream of the feed rollers that iscapable of splitting the textile batt to produce partial thicknesstextile batts, adhesive appliers positioned downstream of the splittingknife that are capable of applying an adhesive to an outer surface ofeach of the partial thickness textile batts, vapor barrier supplypositioned downstream of the adhesive appliers that is capable ofsupplying vapor barrier material that contacts the outer surfaces of thepartial thickness textile batts, and pressure rollers positioneddownstream of the vapor barrier supply that are capable of partiallycompressing the partial thickness textile batts to bond to the vaporbarrier adhesive.

[0010] Further areas of applicability of the present invention willbecome apparent from the detailed description provided hereinafter. Itshould be understood that the detailed description and specificexamples, while indicating the preferred embodiment of the invention,are intended for purposes of illustration only and are not intended tolimit the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The present invention will become more fully understood from thedetailed description and the accompanying drawings, wherein:

[0012]FIG. 1 shows a side or cross-sectional view of a portion of atextile batt;

[0013]FIG. 2 shows two textile batts bonded to vapor barriers to formthe two textile pads;

[0014]FIG. 3 shows an apparatus for forming two textile pads from thetextile batt; and

[0015]FIG. 4 shows a flooring structuring according to one embodiment ofthe invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] The following description of the preferred embodiments is merelyexemplary in nature and is in no way intended to limit the invention,its application, or uses.

[0017]FIG. 1 shows a side or cross-sectional view of an insulative floorbatt 100, according to the teachings of the present invention. Theinsulative floor batt 100 is manufactured from any of a wide variety oftextile compositions comprising, for example, polyester, nylon, acrylic,cotton, polypropylene, denim etc., or combinations thereof, includingboth natural and man-made fibers. Randomly distributed textile andbinder fibers having lengths between {fraction (1/16)} inch to 1.5inches and a denier of between 5 and 12 are used to form a textile batt100, which is processed to form the insulative floor pad 90.

[0018]FIG. 2 shows one embodiment of the present invention where twotextile pads 200′ and 200 are bonded to vapor barrier layers 206′ and206 to form the two textile underlayment pads 210′ and 210. Theresulting pads may be used as a laminate flooring underlayment or as apad for other types of flooring or for other purposes. The textile batt100 is first heated in an oven 110 and compressed to form an insulativefloor pad 90. Optionally, the insulative floor pad 90 can be split intotwo partial pads 200′ and 200, and each pad bonded to a vapor barrierlayer 206′ and 206.

[0019] Each partial thickness pad 200′ and 200 may be of equal thickness(i.e., the textile insulative floor pad is split in half), or may be ofunequal thickness'. The present invention is capable of forming apartial thickness batt of about {fraction (1/16)} of an inch or greater.The starting insulative floor pad 90 may be split longitudinally toprovide two, three or more partial thickness batts.

[0020] The thermoplastic binder fibers and reinforcement fibers are laidrandomly yet consistently in x-y-z axes. The reinforcement fibers aregenerally bound together by heating the binder fibers above their glasstransition temperature. Typically, less than about 20% by weight binderfiber is used, and preferably about 15% binder fiber is used to form theinsulative floor pad 90.

[0021] Thermoplastic binder fibers are provided having a weight of lessthan 0.2 pounds per square foot and, more particularly, preferably about0.1875 pounds per square foot. The remaining reinforcement fiber isgreater than 0.8 pounds per square foot, and preferably 1.0625 poundsper square foot The binder fibers are preferably a mixture ofthermoplastic polymers which consist of polyethylene/polyester orpolypropylene/polyester or combinations thereof.

[0022] The insulative floor pad 90 is formed by heating the textile batt100 in the oven 110 to a temperature greater than about 350° F. and,more preferably, to a temperature of about 362° F. Such heating causesthe binder fibers to melt and couple to the non-binder fibers, thuscausing fibers to adhere to each other and solidify during cooling. Uponcooling, the binder fibers solidify and function to couple thenon-binder reinforcement fibers together as well as function asreinforcement themselves.

[0023] The insulative textile batt 100 is compressed to form theinsulative floor pad 90 so it has a density of greater than about 10pounds per cubic foot. For underlayment floor systems, the insulativefloor pad 90 preferably has a density of greater than about 10 poundsper cubic foot and, more preferably, about 13.3 pounds per cubic footwith a thickness of about ⅛ inch. For insulative floor pad 90 used underceramic tile, the density is greater than about 15 pounds per cubic footand, more preferably, about 18.9 pounds per cubic foot.

[0024] The sound insulating properties of the material as tested underASTME90-97, ASTME413-87 provide that the insulative floor pad 90preferably has a compression resistance at 25% of the original thicknessof greater than about 20 psi and preferably about 23.2 psi, at 30% ofgreater than about 35.0 psi and preferably about 37.0 psi, and at 50% ofgreater than about 180 psi and preferably about 219 psi. The compressionset at a compression of 25% of the original thickness is less than 20%and preferably about 18.8%, and the tensile strength is between about 60and 80 pounds and, most preferably, about 78.4 pounds.

[0025]FIG. 3 shows an apparatus 300 for forming two textile underlaymentpads 210 and 210′ from the insulative floor pad 90. The apparatusincludes a splitting machine 114, a pair of tension rollers 118,adhesive appliers 123, a pair of vapor barrier supply rollers 126providing the vapor barrier layers 206, a pair of pressure rollers 129,and a pair of take-up rollers 132.

[0026] The feed rollers 104 receive the insulative floor pad 90 and passit to the splitting knife 107, where the insulative floor pad 90 issplit into the two partial thickness batts or pads 200′ and 200. Thethickness of each partial thickness pad is determined by both thethickness of the insulative floor pad 90 and the position of thesplitting knife 107 in relation to the feed rollers 104. When thesplitting knife 107 is substantially centered between the feed rollers104, the insulative floor pad 90 will be split into two substantiallyequal partial thickness pads.

[0027] In the present invention, it has been found that the insulativefloor pad 90 may be controllably and accurately split if the feedrollers 104 are positioned within a predetermined distance from thesplitting knife 107. The distance is important because of thecompressible and pliable nature of the insulative floor pad 90. In thepreferred embodiment, the predetermined distance is from about zero toabout two millimeters.

[0028] In a preferred embodiment using the Mercier Turner splittingmachine 114, the splitting machine 114 is modified by adjusting the feedrollers 104 to a position as close as possible to the splitting knife107, and removing feed guides so that the splitting knife 107 may bemoved closer to the feed rollers than would be possible with the feedguides still in place. In addition, the splitting machine 114 ismodified by changing the feed rollers 104 from a serrated surface typewith multiple sections to a smooth surface type of a single piececonstruction.

[0029] The tension rollers 118 maintain a predetermined amount oftension on the two partial thickness pads 200′ and 200.

[0030] The adhesive appliers 123 are downstream of the tension rollers118 and apply adhesive to outer surfaces of the two partial thicknessbatts. In a preferred embodiment, the adhesive appliers 123 spray alayer of adhesive onto the two partial thickness batts. Alternatively,the adhesive appliers 123 may apply the adhesive directly such as, forexample, with wipers or brushes.

[0031] The adhesive is preferably a high viscosity, low melting pointadhesive that is applied hot and forms a bond as it cools (i.e., a “hotmelt” adhesive). Such adhesives are available from H.B. Fuller, fromSwift Adhesive, and from Western Adhesive (the Western Adhesive productis sold under the product name of RHM542.) Alternatively, any otheradhesive capable of bonding the textile batt to the vapor barrier may beused.

[0032] The pair of vapor barrier supply rollers 126 are also locateddownstream of the tension rollers 118 and serve to supply a vaporbarrier layer 206′ and 206 to each of the two partial thickness pads200′ and 200.

[0033] The vapor barrier preferably is a plastic sheet material,typically about ½ to about 1 mil in thickness. The vapor barrier, as thename implies, prevents the travel of vapor (usually water vapor) throughthe textile pads 210′ or 210. In the preferred embodiment, the vaporbarrier layers 206′ and 206 is coextruded polyethylene, butalternatively any flexible vapor barrier of a suitable thickness may beused.

[0034] The pair of pressure rollers 129 are downstream of the adhesiveappliers 123 and the vapor supply rollers 126. The pair of pressurerollers 129 bring together the two partial thickness pads 200′ and 200and the two vapor barrier layers 206′ and 206 to form the two textileunderlayment pads 210′ and 210. The pair of pressure rollers 129 heatand partially compress the batts during the bonding of the adhesive toform the two textile underlayment pads 210′ and 210.

[0035] In the preferred embodiment, the pressure rollers 129 apply about400 psi (pounds per square inch) of pressure to the two partialthickness textile pads 200′ and 200 and to the vapor barrier layers 206′and 206. In addition, the pressure rollers 129 are maintained at atemperature of about 200 degrees Fahrenheit. The heating partiallysoftens or breaks down the vapor barrier to make it pliable and to aidin penetration of the vapor barrier by the adhesive.

[0036] Downstream of the pressure rollers 129 is a pair of take-uprollers 132. The pair of take-up rollers 132 may be used to roll up thefinished textile underlayment pads 210′ and 210. The finished textileunderlayment pads 210′ and 210 may be used as a floor underlayment, alaminate floor underlayment, as part of a paint drop cloth, etc.

[0037]FIG. 4 discloses a floor structure 212 according to the presentinvention. The floor is formed of a sub floor 214, a surface layer 216,and the insulative floor pad 90, which is disposed between said subfloor 214 and surface layer 216. The insulative floor pad 90 is formedby the binder and reinforcement fibers which are distributedsubstantially random in a first plane. The binder fibers are meltable ata predetermined temperature to couple the binding fibers to thereinforcement fibers.

[0038] The floor surface layer 216 can be wood, a wood based laminate,polymer, or ceramic. The binder fibers are thermoplastic and arepreferably selected from the group containing polyethylene, polyester,polypropylene, and mixtures thereof. In situations where the floorsurface layer 216 is ceramic, insulative floor pad 90 functions toreduce the effects of cracking or movement of the sub floor 214 on thesurface layer 216. For example, should the cement sub floor 214experience a horizontal separating crack, the insulative floor pad 90functions to internally distribute strains within the floor structure212. This reduces the amount of stress applied to the surface layer 216,thus reducing crack initiation in either the ceramic itself or itsadhesive grout. Although the insulative floor pad 90 can have adependent vapor barrier layer 206, it is preferred that a floorstructure 212 having a ceramic surface layer 216 utilize an insulativefloor pad 90 with no vapor barrier.

[0039] The description of the invention is merely exemplary in natureand, thus, variations that do not depart from the gist of the inventionare intended to be within the scope of the invention. Such variationsare not to be regarded as a departure from the spirit and scope of theinvention.

What is claimed is:
 1. An insulative textile flooring pad comprising:reinforcement fibers; and binding fibers selected from the groupconsisting of polyethylene, polyester, polypropylene, and mixturesthereof, said pad having a density of greater than about 13 pounds percubic foot.
 2. The insulative textile flooring pad according to claim 1wherein the binding fibers and reinforcement fibers are distributedsubstantially randomly in a first plane.
 3. The insulative textileflooring pad according to claim 1 comprising less than about 20% binderfiber.
 4. The insulative textile flooring pad according to claim 1comprising about 15% binder fiber.
 5. The insulative textile flooringpad according to claim 1 comprising less than about 0.2 pounds persquare foot binder fiber.
 6. The insulative textile flooring padaccording to claim 4 comprising about 0.1875 pounds per square footbinder fiber.
 7. The insulative textile flooring pad according to claim1 comprising less than about 1.2 pounds per square foot reinforcementfiber.
 8. The insulative textile flooring pad according to claim 1having a density of about 18.9 pounds per cubic foot.
 9. A floorstructure comprising: a sub floor; a surface layer; and an insulativepad disposed between said sub floor and surface layer comprising binderand reinforcement fibers distributed substantially random in a firstplane, said binder fibers being meltable at a predetermined temperatureto couple the binding fibers to the reinforcement fibers.
 10. The floorstructure according to claim 9 wherein said surface material compriseswood.
 11. The floor structure according to claim 9 wherein said surfacematerial comprises ceramic.
 12. The floor structure according to claim 9wherein the binder fibers are selected from the group consisting ofpolyethylene, polyester, polypropylene, and mixtures thereof.
 13. Thefloor structure according to claim 9 having a density of greater thanabout 13.3 pounds per cubic foot.
 14. The floor structure according toclaim 9 having a density of about 18.9 pounds per cubic foot.
 15. Thefloor structure according to claim 14 being about {fraction (3/32)} inchthick.
 16. The floor structure according to claim 9 having a compressionresistance at a compression of 25% of the original thickness of greaterthan about 20 psi.
 17. The floor structure according to claim 9 having acompression resistance at 50% of the original thickness of greater thanabout 180 psi.
 18. A floor underlayment for disposal under a floorsurface comprising: less than about 20% thermoplastic binder fibers andmore than about 80% reinforcement fibers; said floor underlayment havinga first surface disposed beneath said floor surface and having a densityof greater than about 13.3 pounds per cubic foot.
 19. The floorunderlayment according to claim 18 having a density of greater thanabout 18 pounds per cubic foot.
 20. The floor underlayment according toclaim 18 wherein the thermoplastic binder fiber is selected from thegroup consisting of polyethylene, polyester, polypropylene, and mixturesthereof.